No way to have your iPad send iMessages from your phone number, but you can have your iPhone send iMessages from your email address. On your iPhone, go into Settings>Messages and on the CallerID option have it send from your email address instead of your phone number. if your iPad is sending from the same email address your messages should come in and be sent from both devices.

Anyone know when Apple is going to merge icloud emails and phone numbers?
In the keynote they mentioned "Phone number and Apple ID merging." Does this mean this will be implemented in Mountain Lion or in iOS 6? If iOS 6, I guess will Mountain Lion users have to wait until the release of iOS 6 to get this feature.

No way to have your iPad send iMessages from your phone number, but you can have your iPhone send iMessages from your email address. On your iPhone, go into Settings>Messages and on the CallerID option have it send from your email address instead of your phone number. if your iPad is sending from the same email address your messages should come in and be sent from both devices.

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